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Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to

information for citizens to secure access to information under the control of public authorities,in order to promote transparency and accountability in the working of every public authority,

and whereas the attached publication of the Bureau of Indian Standards is of particular interest

to the public, particularly disadvantaged communities and those engaged in the pursuit of

education and knowledge, the attached public safety standard is made available to promote the

timely dissemination of this information in an accurate manner to the public.

!"#$% '(%)

!"# $ %& #' (")* &" +#,-.Satyanarayan Gangaram Pitroda

Invent a New India Using Knowledge

/0)"1 &2 324 #' 5 *)6Jawaharlal Nehru

Step Out From the Old to the New

7"#1&"8+9&"), 7:1&"8+9&")Mazdoor Kisan Shakti Sangathan

The Right to Information, The Right to Live

!"# %& ;

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IsnEC 309-1 1988

f ~ X i l c B c ~ T ~

ndian tandardPLUGS SOCKET OUTLETS AND COUPLERS FOR

INDUSTRIAL PURPOSESPART 1 GENERAL REQUIREMENTS

ICS 29.120.30

C BIS 1996URE U OF INDI N ST ND RDSM N K H V N . 9 H DUR SH H Z F R M RG

W DELHI 110002

l gJlst 99 Price Group 15

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Rota lon Machinery Sectional Committee. ET 14

CONTENTSlause age

Scope , .Definitions .

1.2.

I25Generalrequirements .

4. Generalnoteson tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55. Standard ratings . . . . . . . . . . . . . . . . . . . 66. Oassification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67. Marking , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78. Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Protection againstelectricshock , . . . . . . . . . . . . . . . . . . . . . . . 1010. Provision forearthing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11I I. Terminals , . . . . . . . . . . . . . . . . . . . . 1212. Interlocks andretainingdevices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1713 Resistance to ageingof rubberand thermoplastic material . . . . . . . . . . . . . . . . . . . . . 1714. Generalconstruction . 1815. Construction of socket-outlets 1816. Construction of plugs and connectors 2017. Const ruetion of applianceinlets 2118 Degreesof protection 22} . Insulat ion resistaaceand electric strength 2320. Breaking capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2521. Normal operation 2722. Temperature rise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2823. Plexible cables and their connection 2924. Mechanical strength 3225. Screws, current-carrying parts and connections . . . . . . . . 3526. Creepage distances.clearances and distances through sealing compound . . . . . . . . . . . . . . . . . . . . . 3827. Resistance to heat. fire and tracking , 392 . Resistance to rusting _. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 ,rltES .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ; . . . . . . . . 42APPf N X A - Metric and AWGlMCM conductorsize equivalents 57

NAllONAL R)REWORDThisIndian Standard Part 1 is identical to lEe Pub 309-1 1988) covering General requirements of plugs andsocket-outlets and couplers for industrial purposes issued by International Electroteehnical Commission, wasadopted by tile Bureau of Indian Standards on the recommendation of the Wiring Accessories SectionalComm iuee, f14and approvalof tile Electroteehnical Division Council.

standard Part I) ppli s to plugs and socket-outlets. cables couplersand appliance couplers. rated currentDO t exceeding 250 A primarily intendedfor industrialapplication, either indoor or outdoor.

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lS/IEC 3 9 l l ndian Standard

PLUGS. SOCKET-OUTLETS AND COUPLERS FORINDUSTRIAL PURPOSES

PART 1 GENERAL REQUIREMENTSI NTRODUCTION

This standard is divided into several parts :Part General requ irements, comprising clauses of a general character.Subsequent parts Particular requirements dealing with part icular types . The clauses of

these particular requirements supplement or modify the corresponding clauses in Part I Where the text of subsequent parts indicates an addition to or a replacement of therelevant requ irement, test specification or explanation of Part these changes are madeto the relevant text of Part I which then becomes part of the standard. Where nochange is necessary, the words This clause of Part I is applicable are used.

I opeThis standard applies to plugs and socket-outlets, cable couplers and appliance

couplers, with a rated operating voltage not exceeding 690 V d.c . or a.e. and 500 Hz a.c,and a rated current not exceeding 250 A, primarily intended for industrial use, eitherindoors or outdoors.

The list of preferred ratings is not intended to exclude other ratings, requirements forwhich are under consideration.

This standard applies to plugs and socket-outlets, cable couplers and appliancecouplers, hereinafter referred to as accessories, for use when the ambient temperaturedoes not normally exceed 40 C.

The use of these accessories on building sites and for agricultural, commercial anddomestic applications is not precluded.

Socket-outlets or appliance inlets incorporated in or fixed to electrical equipment arewithin the scope of this standard. This standard also applies to accessories intended tobe used in extra-low voltage installations.

This scandard docs 110 apply to alXeSlOries primarily intended for demesne and similar Jeneral purposes .

In locations where special conditions prevail, for example on board ship or whereexplosions are liable to occur, additional requirements may be necessary.

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IS/IEC 3091 9882. DefiDitioD5

Where the terms voltage and current are used, they imply the d.c. or the a.c. Lm .values.

The following definitions apply for the purpose of this standard.The application of accessories is shown in Figure I.

21 Plug and socket outletA means enabling the connection at will of a flexible cable to fixed wiring. consists

of two parts:2 Socket outlet

The part intended to be installed with the fixed wiring.A socket-outlet may also be incorporated in the output circui t of an isolating transformer .

2 1 2 PlugThe part integral with or intended to be attached to the flexible cable connected to

the equipment or to a .connector.22 Cable coupler

A means enabling the connection at will of two flexible cables. consists of twoparts:

22 ConnectorThe part integral with or intended to be attached to the flexible cable connected to

the supply.22 2 Plug

The part integral with or intended to be attached to the flexible cable connected tothe equipment or to a connector.

The plug of a cable coupler is identical the plug of a plug and socket-outlet. In general. a connector hasrhe same contact arrangement as a socket-outlet .

2 3 Appl ianu couplerA means enabling the connection at will of a flexible cable to the equipment. consists of two parts:

231 ConnectorThe part integral with. or intended to be attached to, the flexible cable connected tothe supply.

23 2 Appliance inlnThe part incorporated in, or fixed to, the equipment or intended to be fixed to it.In general . the connector of an appliance coupler is identical to the connect or of a cable coupler n anappliance inlet has the same contact arrangement as a plug.

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IS/IEC JOt1 I )2.4 Rewirable plug or connertor

An accessory so constructed that the flexible cable can be replaced.2.5 Non-rewirable plug or connector

An accessory so constructed that the flexible cable cannot be separated from theaccessory without making it permanently useless .2.6 Mechanical switching device

A switching device designed to close and open one or more electric circuits by meansof separable contacts.

2.7 Switched socket-outletA socket -outlet with an associated switching device to discmne t the supply from the

socket-outlet contacts.2.8 Integral switching device

A mechanical switching device constructed as a p n of an accessory covered by thisstandard.

2.9 InterlockA device either electrical or mechanical which prevents the contacts of a plug from

becoming live before it is in proper engagement with a socket-outlet or connector andwhich either prevents the plug from being withdrawn while its contacts are live or makesthe contacts dead before separation.

2.10 Retaining deviceA mechanical arrangement which holds a plug or connector in position when it is in

proper engagement and prevents its unintentional withdrawal.2.11 Rated current

The current assigned to the accessory by the manufacturer.

2.12 Insulation voltageThe voltage assigned to the accessory by the manufacturer nd to which dielectric

tests clearances and creepage distances are referred.2.13 Rated operating voltage

The nominal voltage of the supply for. which the accessory is intended to be used .2.14 Basic insulation

The insulation necessary for the proper functioning of the accessory nd for basicprotection against electric shock.

2.15 Supplementary insulation protective insulation An independent insulation provided in addition to the basic insulation. in order to

ensure protection against electric shock in the event of a failure of the basic insulation.

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ISIIEC Jot I 19 )2 16 Double insulalion

Insulation comprising both basic insulation and supplementary insulation.2 17 Reinforced insulalion

improved basic insulation with such mechanical and electrical qualities that itprovides the same degree of protection a ainst electric shock as double insulation.

2 18 TerminalA conductive part provided for the connection of a conductor to an accessory.

2181 Pillar terminal terminal in which the conductor is inserted into a hole or cavity, where it is

clamped under the shank of the screw or screws. The clamping pressure may be applieddirectly by the shank of the screw or through an intermediate clamping member to whichpressure is applied by the sfiank of the screw see Figure 14a).

2 182 Screw terminalA terminal in which the conductor is clamped under the head of the screw. The

clamping pressure may be applied directly by the head of the screw or through anintermediate Part. such as a washer, clamping plate or anti-spread device see Figures 14band 14c).

2183 iu terminalA terminal in which the conductor is clamped under a nut. The clamping pressure

may be applied directly by a suitably shaped nut or through an intermediate part, suchas a washer, clamping plate or anti-spread device see Figure 14d).

2184 Saddle termineA terminal in which the conductor is clamped under a saddle by means of two ormore screws or nuts see Figure 14e).

2 185 Lug terminalA screw terminal or a stud terminal, designed for clamping a cable lug or bar bymeans of a screw or nut see Figure 14f).

2 186 Mantle terminalA terminal in which the conductor is clamped apinst the base of a slot in a threaded

stud by means of a nut. The conductor is clamped against the base of the slot by asuitably shaped washer under the nut. by a central peg if the nut is a cap nut, or byequally effective means for transmitting the pressure from the nut to the conductorwithin the slot see Figure 14 .

219 Clamping unilThe part of a terminal necessary for the clamping and the electrical connection of theconductor.

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IS/lEe 3091 988:?O rypt test

A test of one or more n i < e ~ made to a ce rt ai n de sign to ~ h 0 ' that the meetcer ta in spec ificauons .

3. General requirementsAccessories shall he so designed and constructed that in normal use their performance

is r el ia bl e and without danger to the user or surround ings .

In general. compliance is checked by currying out at the tests specified

4. General notes on tests4.1 Tests according to this standard are type tests. f a part of an accessor: has previouslv

passed tests for a given degree of severity , the relevant type tests shall not be repeated the severity is not greater.

4.2 Unless otherwise specified, the samples are tested as delivered and under normal conditionsof use, at an ambient temperature of 20 5 C: the tests are made at rated frequency .

4.3 Unless otherwise specified, the tests are carried out in the order of the clauses of thisstandard.

4.4 Three samples are subjected to all the teJIJ however, the tests of Clauses 20. 11 nd have to be made with both d.c. and a.c., the test h a.c. is made on three additionalsamples.

4.5 Accessories are deemed to comply with this standard if no sample fails in the complete seriesof appropriate tests. f one sample fails in a lest, that test nd those preceding which mayhave influenced the test result are repeated on another set of three samples. all of whichshall then pass the repeated tests.

In general . it will o n ly he necessary to repeat t h e te l wh ich c au se d the failure . unle. . Ih e ....mple fa,l, m oneo f the t es ts of C la u ses 21 and 22. In whIch case the tes are repeated from Ihat f nau 20 nn wa rd ,

The applicant may submit . together with the first set o f samples , the add n io na l S . . hrch ma y he wantedshould one sample fall . The t es ting s ta tion w,lI then . . . l1hOUI further re que st . test the a dd l ll lOa l samples and willreject only if a fun he r fa. l ur e occur s. the addit ional .a of samples is not submitted al the same ume, thefailure of one sample will entail a rejection .

4.6 When the tests are carried out with conductors, the latter shall ecopper nd comply witht sc Publications 227. 228 nd 245-4.

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IS/IEC 309-1 19885. Standard ratings5.1 Preferred rated operating voltage ranges and voltages are :

20 V to 25 V40 V to 50 V100 to 130 V

200 V to 250 V277 V

380 V to 415 V440 V to 460 V480 V to 500 V600 V to 690 V

5.2 Preferred rated currents are given in the following table:

T L I

Series I Series II

16 2032 3063 60 25 100250 200

6. Classification6.1 Accessories are classified:6 according to purpose : plugs socket outlets connectors appliance inlets;

6.1.2 according to degrees of protection : either in accordance with l Publ icat ion 529according to degrees of protection against moisture:

ordinary accessories; splashproof accessories; watertight accessories.

For new designs degrees of protection according to Publication 529 shall be used.

IPXO/ordinary accessories have no special protection against moisture. and the y need not have lids.

In some countries IPXO / ordinary accessories are not allowed.6.1.3. according to earthing facilities:

accessories without earthing contact ; accessories with earthing contact;

6.1.4 according to the method of connecting the cable: rewirable plugs and connectors; non rewirable plugs and connectors;

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IS/lEe 309-1 19886.1.5 according to interlocking facil ities:

- accessories without interlock, with or without integral switching device;- accessories with mechanical interlock;- accessories with electrical interlock.

7. Marking7.1 Accessories shall be marked with:

- rated current s) in amperes;- rated operating voltage s) or range s) in volts;- symbol for nature of supply, if the accessory is not intended for both a.c. and d.c., or

is intended for a.c. with frequencies other than 50 Hz or 60 Hz, or if the rating isdifferent for a.c. and d.c.;- rated frequency if exceeding 60 Hz;- either the name, trade mark or identification mark of the manufacturer or of the

responsible vendor ;- type reference , which may be a catalogue number;- symbol for degree of protection as applicable;- symbol indicating the position of the earthing contact or the means used for

interchangeability, if any.Opt ionally, the ins ulation voltage may be marked. ompliance is checked by inspection

7.2 When symbols are used, they shall be as follows:A .y .Hz .

@ or J .IPXO or no symbol .IPX4 or one drop in a triangle) .IPX7 or M t wo d rop s) . .IPXX relevant figures) .

amperesvoltshertzalternating currentdirect currentearthordinary constructionsplashproof construction

watertight construction

other constructions

For the marking of rated current s) and r at ed op er at in g voltage s) or range s), figuresmay be used alone.

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IS lEe 309-1 988The figure for d.c. rated operating voltage, if any. shall then be placed before the

figure for the a.c. rated operating voltage, and separated from it by a line or a dash .

ompliance is checkedby inspection

7.3 For socket-outlets and appliance inlets, the marking for rated current, nature of supply, ifnecessary, and either the name , trade mark or identification mark of the manufacturer orthe responsible vendor shall be on the main part , on the outside of the enclosure, or onthe lid, if any, if the latter cannot be removed without the aid of a tool.

Except for flush-type socket-outlets and appliance inlets, these markings shall be easilydiscernible when the accessory is mounted and wired as in normal use, if necessary afterremoval from the enclosure. The marking, if any , for the insulation voltage shall be onthe main pan ; it shall not be visible when the accessory is mounted and wired as innormal use.

The marking for rated operating voltage, type reference, the symbol for degree ofprotection, if required, and the symbol indicating the position of the earthing contact orthe means used for interchangeability, if any, shall be on a place which is visible afterinstallation of the accessory, on the outside of enclosure or on the lid, if any, if thelatter cannot be removed without the aid of a too l.

With the except ion of the type reference, these markings shall be easily discerniblewhen the accessory is mounted and wired as in normal use.

ompliance is checkedby inspectionThe tu m ma in pan o f a socket-outlet or an appliance inlet means the pan carrying the contacts.

The type reference may be marked on the main pan .

7.4 For plugs and connectors, the marking specified in Sub-clause 7.1, with the exception ofthe marking for insulation voltage, if any , shall be easily discernible when the accessoryis wired ready for use.

The marking for insulation voltage, if any, shall be on the main part it shall not bevisible when the accessory is mounted and wired as in normal use.

The term ready for use does not imply that .he plug or connector is in .engagement with its complementaryaccessory.The term main part of a plug or a connector means the part carrying the contacts . ompliance is checked by inspection

7.5 For rewirable accessories. the contacts shall be indicated by the symbols :

- for three-phase, the ~ m o s , L2, LJ, or I, 2, 3 for the phases, N for neutral, ifany , and the symbol or...l- for ear th :

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lS/IEC 309-1 1tfor two-pole, which may he used for hoth a.c. and d .c., one symbol for one of thelive poles and the symbol @ or J for earth. i f any ;

- for a period of time the marking R I. S2. T3 may be used instead of , L2. L3.

These symbols shall be placed close to the relevant terminals ; they sha ll not be placedon screws. removable washers or other removable parts.

The term inals for pilot cond uctor s are not required 10 be indrcated,The figu res used wuh the let ters be wruien a an index . It IS recommended thaI here pracuceble the

symbol should be usedCompliance is checked by inspection.

7.6 Marking shall be indelible and eas ily legible.Compliance is checked by inspection n by the following test :After the humidity treatment of Clause /8 . the marking rubbed v i t f o r o l U ~ ~ by h n for

15 s with a piece of cloth soaked in water n again for 5 s with a piece of doth soakedwith petroleum spirit.

Special attention is paid to the marking of the name, trade mark or identification markof the manufacturer or the responsible vendor n to that of the nature of S U P P ~ Y an .

A special lest for checking the indel ib il ity of these marking IS under cons ideration

7.7 If in addition to the marking prescribed, the rated operating voltage is indicated bymeans of a colour, the colour code shall be as shown in Table II. An indicating colour.if different from that of the enclosure, shall be used only if it can be easilydistinguished.

T BLE IIRated operating voltage Colour V

20 0 2S Violel40 10 SO I While100 10 130 Yellow200 10 I BIlK380 10 480 I Red 10 690 Black

II For frequencies over 60 Hz up 10 and including SOO Hz. thecolour green may be used, if necessary, in combination ilh lhecolour for lhe rated operating vollqe .

II In countries ....here aa:asories of Series current ratinp arewed. th e colour orange is reserved for ~ V a.c , and lhecolou r grey is reserved for 277 V a.c. accalOries.

8. ime sioel8.1 Accessories shall comply with the appropriate standard sheets, if any .

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IS IE 3 9 1 1 )

. 8.2 t shall not be possible to engage plugs or connectors with or applianceinlets having different ratings or having different contact combmatlOns.In addition the design shall be such that improper connections shall not be possible

between:_ the earth and o r pilot plug contact and a live socket contact or a live plug contact andthe earth and or pilot socket contact;

_ the phase plug contacts and the neutral socket contact if any;_ a neutral plug contact and a phase socket contact.

Compliance is checked by inspection8.3 t shall not be possible to make single pole connections between plugs and socket outlets

or connectors or between appliance inlets and connectors or socket outlets.

Plugs and appliance inlets shall not allow improper connections with socket outletscomplying with l EC Publication 83 or with connectors complying with l Publication 320.

Socket outlets and connectors shall not allow improper connections with plugscomplying with l Publication 83 or with appliance inlets complying with l Publi-cation 320.

Improper connections include single pole connections and other connections which donot comply with the requirements for protection against electric shock.

Compliance is checked by inspection

9. ProtectioD u electric: shock9.1 Accessories shall be so designed that live parts of socketoutlets and connectors when

they are wired as in normal use. and live parts of plugs and appliance inlets when theyare in partial or complete engagement with the complementary accessories are notaccessible.

In addition it shall not be possible to make contact between a contact of a plug orappliance inlet and a contact of a socket outlet or connector while any contact isaccessible.

Compliance is checked by inspection and necessary by a test on the sample wired asin normal use

The standard test finger shown in Figure is applied in every possible positron anelectrical indicator with a voltage not less than 40 being used to show contact with therelevant part

N ulral contacts and pilot contact s of socketoutlet s and connect ors are deemed to be live parts .

9.2 Accessories with earthing contact shall be so designed that : when inserting the plug or connector. the earth connection is made before the phase

connections nd neutral if any are made;

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IS/U:C JOt1- when withdrawing he plug or connector. the phase connections and neutral, if any.

are broken before the earth connection broken.9.3 shall not be possible to inadvertently assemble the pan carrying plug contacts into the

enclosure of a socket-outlet or connector.Compliance is checked bv manual test.

10. Proyision for earthing1 1 Accessories with earthing contact shall be provided with an earthing terminal. Metal-clad

fixed accessories with an internal earthing terminal can, in addition, be provided with anexternal earthing terminal, which, except for flush type socket-outlets, shall be visiblefrom the outside.

Earthing contacts shall be directly and reliably connected to the earthing terminals,except that the ear thing terminal of socket-outlets incorporated in the output circuit of anisolating transformer shall not be connected.

Compliance is checked by inspection.10.2 Accessible metal parts of accessories with earthing contact, which may become live in

the event of an insulation fault, shall be reliably connected to the internal earthingterminal s) by construction.

For the purpose o th is requirement. screws or fix in . bales, covers and the like an noc ~ m to heaccessible pans which may become live in the event o an insulation fault .

accessible metal pans are screened rom live pans by metal paru which are connected to an eanhiterminal or earthing contact . or if they are separated from live pans by double insulation or reinforoedinsulatioa, they are nOI . for the purpose of th is requirement. regarded as likely to become hve in the event of aninsulation Iault .

Compliance s checked by inspection n by the following test:A current of 25 A derived from an a.c. source having a no load voltage not exceeding 11 V

s passed between the earthing terminal n each of the accessible metal p ns in tum .

h voltage drop between the earthing terminal n the accessible metal part is measured.n the resistance calculated from the current n this voltage drop.

In no case shall the resistance exceed 0.05 Care should he taken thai rhe contact resistance between lhe tip of the meuurinll probe and the metal part

under lest does not influence the test results ,

10.3 Earthing contacts shall be capable of carrying a current equal to that specified for thephase contacts without overheating.

Compliance is checked by the tes of Clause 22.10.4 Earthing contacts shall be so shrouded or guarded that they are protected apinst

mechanical damage.Compliance is checked by inspection .This requirement precludes the use of SIde earthing contacts.

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IS lEe 309-1 ( 1988) Terminal..

. h . I in which connection IS made bvRewirahle accessories shall be provided t terrmna s Jmeans of screws. nuts or equally effective devices.

Compliance is checked by inspection.Requirements for screwless terminals are under consideration.

II :? Parts of terminals. other than screws. nuts. washers. stirrups. clamping plates and thelike. shall be either of :- copper;_ an alloy contairung at least 58 copper for parts that are worked cold or at least 50

copper for other parts;_ or other metal not less resistant to corrosion than copper and having mechanical

properties no less suitable.Steel screws shall be adequately protected against corrosion.Compliance is checked by inspection n by chemical analysis.A relaxat ion of the requ irement for pans of term inals is under considerat ion.

.3 If the body of an earthing terminal is not part of the metal frame or housing of theaccessory, the body shall be of material as prescribed in Suh-c1ause 11.2 for parts forterminals. If the body is part of the metal frame or housing, the clamping screw or nutshall be of such material.

If the body of the earthing terminal is part of a frame or housing of aluminium oraluminium alloy, precautions shall be taken to avoid the risk of corrosion resulting fromcontact between copper and aluminium or its alloys.

The requirement regardmg the avoidance of the risk of corrosion does not preclude the use of adequatelyenured mt'IJI \ere', , ' o r nut

Compliance is checked bv inspection n by chemical analysis.

.4 Terminals shall allow the connection of conductors having nominal cross-sectional areasas shown in Tahle III.For terminals other than lug terminals compliance is checked by the following test n bythe tests of Sub clauses 11.7. 11.8 n 11.9.Gauges as specified in Figure IJ. having a measuring section for testing the insertibility

of the maximum specified cross sectional area of Table lJ shall be able to penetrate intothe terminal aperture under their own weight to the designated depth of the terminal.

For pillar terminals in which the end of a conductor is not visible, the hole toaccommodate the conductor shall have a depth such that the distance between thebottom of the hole and the last screw will be equal to at least half the diameter of thescrew. and in any case not less than 1.5 mm.

Compliance s checked by inspection.

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T LE ize connect ble conductors

r - -- .- .- - - ---.--_ ._...---.Rating 01 the accessory Internal connection II xtern l rthing ronnccnon Iff t .. . - --f-- ..- - .....- .-. ..

Yoltagev

Current

A

Flexible cab les lor p lugsand connectors

Solid or stranded cableslor appliance inlets 11

Solid or stranded cableslor sockcr-ourlets

AW j /MC\1mm '41 0 104 to 10

12 10 812 to 8

AWG /MCMm410 104 10 10

2030

Series II1632

Series INot exceeding 50

- ----- -------- r--.- ----f-------. ---------j-- - - ,..-- - - --- _ . ... ..- . ..- ....AWG /MCM

~ f _ _ 12 to 812 to H

r .- -+ --- - - . + - - - +- - - - +-- .+--- .- - ..- ..... ..-._- ..10H444

16 10 121410 10101066 10 2

00 to 0000

I to 2,52.5 to 6610 1616 to 5070 to 150

Exceeding 5016 I 20 10 4 16 10 12 1 10 10 14 10 HU. u to 25 I0 to 4

125 i 100 10 70 I 4 to 0 _ ~ __ ~ _ OO - -- 10_ 85 ~ Terminals l or pi lo t conductors, an ) . sha ll a llow the connecnon 01 conductors having the same nominal crow-cect ional a reas as the mter nal termina l, 01 I > A aete w ,

h,, tng rated operating soilages exceeding 50 V11 C1a.ssillcatwn 01 conductors : according t o 1EC Puh lica tion 218 Clause 2. solid (Cla.u I); stranded ICias s 2) ; [ le .. hle eI .. 5

The nominal cross -sectional areas 01 conducto rs arc g iven in square mill imeters (rnm ') . AWG /MCM values are considered as equivalent to mm ' (or the purpose 0 / IhIS standard

Aw n , American Wire Gauge i s a sys tem d Idenl llyin wires In 'which the diameters are lound In geometric progrewion between slle 16 and sile 0000

MCM : Mille Circular M,t. denotes circle surface unit . I MCM 150 mm ' lor 200 A Serie s II devices .

0.5067 mm . --

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IS/lEe 3M-I 1 )f h I h II accept conductors havingFor terminals complying with Figure 14 .t e ug s anominal cross-sectional areas within the appropnate range specified in the Table Ill

Terminals that cannot be checked by the gauges specified in Figure 13 are tested bysuitabl y shaped gauges having the same cross-section as those given in Table III.

.5 Terminals shall have appropriate mechanical strength.Screws and nuts for clamping shall have an ISO thread or a thread comparable in

pitch and mechanical strength.Provtsionally. SI. BA and UN threads are considered as being comparable in pitch and mechanical strength.Compliance is checked by inspection. measurement and the test of Sub-clause 25. I. In

addition to the requirements of Sub-clause 25.I the terminals shall not have undergonechanges after the test that adversely affect their future use.

11.6 Terminals shall be properly fixed to the accessory and shall not work loose when theclamping screws or nuts are tightened or loosened.

Screws and nuts for clamping the conductors shall not serve to fix any othercomponent.

The clamp ing means for the conductor may be us to stop rotation or displacement of the plug or socketcontacts.

Compliance is checked by inspection and necessary by the test of Sub-clause 25.1.These requi remen ts do not preclude terminals that arc floating or terminals so designed that rotation or

displacement of the terminal is prevented by the clamping screw or nut provided that their movement isappropriately limited and does not impair the correct operat ion of the accessory.TermlOal\ may be prevented from workina loose by Iixing with two screws by filling with one screw in arecess such that there is no appreciable play or by o ther suitable tneans.Covering with sealing compound without other means of lockina is not deemed to be sufficient. Self-hardeningresins may. however be used lock terminals which are not subject to torsion in normal use.

Terminals shall be so designed that they clamp the conductor between metal surfaceswith sufficient contact pressure and without damage to the conductor.

Compliance i.f checked by inspection and the type tests of the terminals of Sub -clauses 11.8and 11.9. applied to three separate terminals.

11.8 First testVt Ji/it ation is made successiveiy with conductors of the largest and smallest cross-sectional

areas specified in Table 1/1 using rigid conductors for terminals of socket-outlets orappliance inlets and flexible conductors for terminals of plugs or connectors.

The conductors shall be connected to the clamping unit and the clamping screws or nutstightened to two-thirds of the torque indicated in Table XIV Each conductor is subjected toa pull according to the value in Table -I. exerted in the opposite direction to that inwhich the conductor was inserted. The puJl is applied without jerks for J min. The maximumlength of the test conductor shall be I m.

During the test the conductor shall not slip out o f the terminal nor shall it break at orin. the clamping unit.

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lSI1EC )091 IT II IVI

mrn h lf

30405050eo9 J

100ItlO11

-le10III5070150185

. . ..- - - . -_ ._ - -- - - _.-- -- --- - --- - - - - - _._- - - - -- I I 5

11.9 Second testThis test is carried o first with the smallest cross-sectional area and then with the

largest cross-sectional area of the relevant values in Table for rigid and flexibleconductors. The clamping screws or nuts are tightened with the torque according to Table XVThe terminal is fasten ed to a conductor whose length is at least mm longer than theheight specified in Table V . and is secured rigidly in a vertical position simulating actualservice conditions. The f ree end of the cable is passed through a bushing of the sizespecified in Table I V-II. The bushing is attached to an arm. driven by a motor at a rateof approximately 9 r.p.m. and in such a manner that the centre of the bushing is made todescribe a circle in a horizontal plane see Figure 15

The circle shall have a diameter of 2 mm and irs centre shall be venically belowthe centre of the conductor opening in the terminal. The bushing is lubricated to preventbinding. twisting or rotation of the insulated cable. A weight as specified in Table IV-II i suspended from the f ree end of the conductor. The duration of the test is I min.

During the test the conductor shall not pull out of the clamping unit.Breaking of the conductor or of any strand of a stranded conductor is determined b.

examining the entire terminal while the conductor is still connected aft er the test. Theconductor or strand of a stranded conductor shall not be visibly detached.

T LE IV-IIDiameter of I -- -- -- - - lCross-sectional area Height Iof a rigid conductor bushing i WeIghI Imm mm mm I N I6.5 240 15 II i

1.5 6.5 260 I 20 I2.5 9.5 280 25 II 9.5 280 I 25I I9 5 280 I JOIII 9.5 280 I 4 I16 13 300 50 I5 13 300 I 50SO 16 SO I 8070 20 370 I 80 IS 22 400 I 110 I185 26 430 I Revisio n of this test is under consideration.

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IS/lEe )091 1988 )shall be used only for acce ssories having a rated current of at least .10 Lug terminals J J. I are provided, they shall be fitted with spring washers or equally63 A: if such terrnma s

effective locking means .Compliance is checked by inspection.

.11 Each terminal shall be located in proximity to its corresponding terminal o ~ t r m i n l ~of different polarity, and to the in ternal earthing terminal, if any, unless there IS a sountechnical reason to the contrary.

Compliance is checked by inspection. .12 Clamping screws or nuts of earthing terminals shall be adequately locked against

accidental loosening, and it shall not be possible to loosen them without the aid of atool.

Unless two screws in pillar type terminals are used, a test is required to prove thelocking capabilities .

A test is under consideration.Compliance s checked by inspection and by manual test

11.\ 3 Terminals shall be so located or shielded that :_ screws becoming loose from the terminals cannot establish any electrical connection

between live parts and metal parts connected to the earth ins terminal;_ conductors becoming detached from live terminals cannot touch metal parts connected

to the ear th ing terminal:_ conductors becoming detached from the ear th ing terminal cannot touch live parts

This requirement applies also 10 terminals for pilot conductors.Compliance is checked by inspection and by manual test.

11.\ 4 When the conductors have been correctly fitted, there shall be no risk of accidentalcontact between live parts of different polarity or between such parts and accessiblemetal parts, and should a wire of a stranded conductor escape from a terminal thereshall be no risk that wires emerge from the enclosure.

The requirement with regard to the risk of accidental contact between live parts andacce ssible metal parts does not apply to accessories having rated voltages not exceeding50 V

Compliance is checked by inspection and. where the risk of accidental contact between liveparts and other metal parts is concerned. by the following test.

An 8 mm length of insulation is removed from the end of a flexible conductor having across-sectional area in the middle pf the range specified in Sub-clause 11.4. One wire of thestranded conductor is left free and the other wires are fully inserted into n clamped inthe terminal. The free wire is bent. without tearing the insulation back. in every possibledirection. but without making sharp bends round barriers.

The free wire of a conductor connected to a live terminal shall neither touch any metalpart whi h is nor a live part nor emerge from the enclosure and that of a conductorconnected to the earthing terminal shall not touch any live part.

If necessary the lest is repealed with the free ire in another position.

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Ism:c J091 191112. Interlocks12.1 An interlock shall he incorporated in socket-outlets and connectors not comply 109 with

the appropriate tests for breaking capacity and normal operation .

interlocks shall he linked with the operation of a switching device so thai the plugcan neither be withdrawn from the socket-outlet or connector while the contacts arealive. nor be inserted while the switching device is in the ON position.

Socket-outlets and connectors shall be so designed that . after engagement with anycomplementary accessory. the interlock operates correctly .

The operation of an inter lock shall not be impaired hy normal wear of the portion ofthe plug used for interlocking.

The mechanical switching device for a mechanical interlock may be incorporated 10 thesocket-outlet or connector .Compliance is checked by inspection after the tests of Clause 2/ .

12.2 Mechanical switching devices for interlocked a.c. switched socket-outlets shall be in autilization category of at least AC 22 according to I EC Publication 408.

Mechanical switching devices for interlocked d.c. switched socket-outlets or connectorsshall be of category of duty according to the application .

Accessories having an integral switching device and operated by the plug need notcomply with requirements of I EC Publication 408 but shall be in accordance withClauses 20 and 2 I of this standard .

Compliance is checked by inspection. by m ~ u r m n t and bv tests.

13. Resistance to ageing of rubber and thermoplastic materialAccessories with enclosures of rubber or thermoplastic material, and parts of

elastomeric such as sealing rings and gaskets. shall be sufficiently resistant to ageing.

Compliance is checked by an accelerated ageing test made in an atmosphere having thecomposition and pressure of the ambient air.

The samples are suspended freely in a heating cabinet, ventilated by natural circulation.The temperature in the cabinet and the duration of the ageing test are ,

70 2 C and 10 days 240 h}. for rubber:.80 and 7 days /68 h for thermoplastic material.After the samples have been allowed to attain approximately room temperature. they are

examined and shall show no crack visible to the naked ere. nor shall the material havebecome sticky or greasy.

After the test. the samples shall show no damage which would lead 10 non-compliancewith this standard.

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IS/lEe 309 1 9 )If there is a doubt as to whether the material has become s ticky the sample is placed on h r in the other pan is loaded with a mass equal to the massone oj t e pans OJ a a ance a the sample plus g Equilibrium is then restored by pressing the sample with the

forefinger wrapped in a dry piece coarse woven clothNo trace the cloth shall remain on the sample and the material the sample shall

not stick to the clothThe use of an electr ically heated cabinet is recommended.

~ t u r circulat ion may be prov ided by holes in the walls of the cabinet.

14 Geller.1 collStructlon14.1 Accessible surfaces of accessories shall be free from burrs, llashes and similar sharp

edges.Compliance is checked by inspection

14.2 Screws or other means for fixing the part carrying the socket-outlet contact or the partcarrying the plug contact to its mounting surface , in a box or in an enclosure, shall beeasily accessible.These fixings and those which fix the enclosure shall not serve any other purpose

except in the case whereby an internal earthing connection is established automaticallyand in a reliable way by such a fixing.Compliance is checked by inspection

14.3 It shall not be possible for the user to alter the posinon of the earthing contact, or ofthe neutral contact. if any. in relation to the means of non-interchangeability of thesocket-outlet or connector, or in relation to the means of non-interchangeability of theplug or appliance inlet.

Compliance is checked by manual test to ensure that only one mounting position ispossible14.4 Socket-outlets and connectors when mounted as in normal use and without a plug in

position shall ensure the degree of protection specified on its marking.

In addition. when a plug or appliance inlet is fully engaged with the socket-outlet orconnector. the lower degree of protection of the two accessories shall be ensured.Compliance is checked by inspection

15. Coatnc:tiotl of socket-oatlets15.1 Contacts shall be so designed as to ensure adequate contact pressure when completelyengaged with the corresponding plug.

Compliance is checked by the temperature rise test Clause 22

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IS/IEC Ot I15.2 The pressure exerted netween the socket lind plug contacts shall not be so great as to

make insertion and withdrawal of the plug difficult . It shall not be possible for the plugto work out of the socket outlet in normal use.

Compliance is checked by inspection.

15.3 Socket outlets shall be so constructed as to permit : the conductors to be easily introduced into the terminals and secured therein; the correct positioning of the conductors without their insulation coming into contact

with live parts of a polarity different from that of the conductor ; the covers or enclosures to be fixed easily after connection of the conductors.

Compliance is checked by inspection and by an installation test it l conductors of thelargest cross sectional area specified in Table ll

15.4 Enclosures and parts of a socket outlet providing protection against electric shock shallhave adequate mechanical strength: they shall be securely fixed in such a way that theywill not work loose in normal use. It shall not be possible to remove these parts withoutthe aid of a tool.

Compliance is checked by inspection.15.5 Cable entries shall allow the introduction of the conduit or the protective covering of

the cable so as to afford complete mechanical protection.Compliance checked by inspection and by an installation test with conductors of the

largest cross sectional area specified in Table 15.6 Insulating linings. barriers and the like shall have adequate mechanical strength and shallbe fixed to the metal casing or the body in such a way that either they cannot be

removed without being seriously damaged or be so designed that they cannot be replacedin an incorrect position.

Compliance is checked by inspection and by the tests of Sub clause 18.2 and Clause UThe use of selfsetting varnish is allowed for fi in insulatin. ininp.

15.7 When a plug is not engaged socket outlets shall be totally enclosed when fitted withscrewed conduits. or polyvinyl chloride sheathed cables. The means for achieving totalenclosure and that for ensuring the marked degree of protection. if any. shall be securelyfixed to the socket outlet. In addition. when a plug is completely engaged. the socket-outlet shall incorporate means for ensuring the marked degree of protection.

Lid springs. if any shall be of corrosion resistant material such as bronze. stainlesssteel or other suitable material adequately protected against corrosion.

Socket outlets splashproof or up to and including IPX4 designed for only onemounting position may have provision for opening a drain hole at least 5 mm indiameter or 20 mm/ in area with a width of at least 3 mm which is effective when thesocket outlet is in the mounting position.

Compliance checked by inspection. by measurement and by the tests of Clauses 18. 19and 21.

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IS/lEe 3091 19I he ta l enc losure and the marked degree of pr otection may be ac hieved by means o f a cover.A draln.hole In the back of the enc losure of a socket-outlet . splashproof or u p to an d i nc lu di ng IPX4 intended

to h mo un ted o n a ver tical wall is deemed to be ef fective onl y If the desi gn o f th e encl osure en sures aclea ra nce a t lea.1 5 mm frum the wall . or prov ides a dra inage cha nnel of at lea st the s rze specified,

15.8 Socket-outlets having rated operating voltages exceeding 50 V shall be provided withearthing contacts.Compliance is checked by inspection

16. Coostruction of plugs n ecaeeeeors16.1 The enclosure of plugs and connectors shall completely enclose the terminals and the

ends of the flexible cable.The construction of rewirable plugs and connectors shall be such that the conductorscan be properly connected and the cores kept in place so that there is no risk of contact

between them from the point of separation of the cores to the terminals.

Accessories shall be so designed that they can only be reassembled so as to ensure thecorrect relationship between the components as originally assembled.

Compliance checked inspection and necessary by manual test16.2 The various parts of a plug or connector shall be reliably fixed to one another in such

a way that they will not work loose in normal use. It shall not be possible to dismantleplugs or connectors without the aid of a tool.Compliance is checked by manual test and by the test of Sub clause 24 3

16.3 If an insulating lining is provided, it shall have adequate mechanical strength an d shallbe secured to the enclosure in such a way that either it cannot be removed withoutbeing seriously damaged or it is so designed that it cannot be replaced in an incorrectposition.

Compliance is checked by inspection n by the tests of Sub clauses 18.2 n 24 3The use o f self setting varnISh IS allowed for fixing i ns ul at in g linings .

16.4 Plug contacts shall be locked against rotation and shall not be removable withoutdismantling the plug .Compliance is checked by inspection and by manual testCo ntacts of r1utl may be ei ther floating or fit

16.5 Contacts of connectors shall be self-adjusting so as to ensure a de qua te contact pr ess ur e.

Contacts other than the earth contact shall be floating.Earth contacts need not be floating provided that they have the necessary resilience inall directions.Compliance checked by inspection n by test

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lSIlEC 3091 191116.6 The pressure exerted by the contacts of connectors on the plul contacts shall not be so

great as t make insertion and withdrawal of the plug difficult. It shall not be possiblefor the plug to work out of the connector in normal use.

Compliance is checked by inspection16.7 Plugs shall incorporate means for ensuring the marked degree of protection against

humidity when in complete engagement with the complementary accessory .t shall not be possible to dismantle this means without the aid of a tool.Compliance is checked by inspection and by the tests of Clauses 18 and 19

16.8 Connectors shall be totally enclosed when fitted with a flexible cable as in nonnal useand when not in engagement with a complementary accessory. In addition they shall incorporate means for ensuring the marked degree of protection when in completeengagement with the complementary accessory:

The marked degree of protection against humidity wben the complementary accessory i. nOl in position maybe achieved by means of a lid or cover.

The means for ensuring the marked degree of protection shall be securely fixed to theconnector.

Lid springs shall be of corrosion-resistant material such as bronze stainless steel orother suitable materials adequately protected against corrosion.

Compliance is checked by inspection and by the tests of Clauses 18 /9 and 2/16.9 Plugs and connectors having rated operating voltages exceeding V shall be provided

with earthing contacts.Compliance is checked by inspection

17. Construction of appliaace lalets 7 Plug-contacts shall be locked against rotation and shall not be removable without the aid

of a tool.Compliance is checked by inspection and by manua testContacts may be ei ther f loat in. or filled.

17.2 Appliance inlets shall incorporate means for ensuring the marked degree of protectionagainst humidity when an appropriate connector is completely enpaed

t shall not be possible to dismantle this means without the aid of a tool.Compliance is checked by inspection and by the tests Qauses 18 and

17.3 Appliance inlets having rated operating voltage exceeding V shall be provided withearthing contacts.

Compliance is checked by inspection;

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l

IS l e 309-1 lIll. Degrees of protection

Accessories shall have the degrees of protection marked on the products.Compliance is checked by the appropriate tests mentioned in the sub-clauses below.

h tests are made on accessories fitted with the cables or conduits for which they aredesigned. sere ed glands and fixing screws of enclosures and covers being tightened with atorque equal to two-thirds of that applied in the tests of Sub-clause 24.5 or 25.1. asappropriate.

Screwed caps. if any. are tightened as in normal use.SMket-outlets are mounted on a vertical surface so that the open drain-hole. if any. is in

the lowest position and remains open.Connectors are placed in the most unfavourable position and the drain-hole. if any.

remains open.SMut outlets and connectors are tested with and also without . the complementaryaccessory in engagement. the means for ensuring the required degree of protection against

moisture being positioned as in normal use.Plugs and appliance inlets are only tested when in engagement with the complementary

accessory.18.2 Accessories marked with IP symbols shall be tested in accordance with Sub-clause 18.1

and l e Publication 529.Immediately after the tests, the- samples shall withstand the electric strength test

specified in Sub-clause 9.3, and inspection shall show that water has not entered thesamples to any appreciable extent and has not reached Jive parts.

J8.3 Accessories marked with drop symbols shall be tested in accordance with Sub-clauses 18.1and 18.4.

18.4 The enclosure of splashproof and watertight accessories shall provide the degree ofprotection in accordance with the classification of the accessory.

a Sp/4sltproof accessories are sprayed with water for 10 min by means of the sprayapparatus. shown in Figure J. which comprises a tube formed into a semi-circle. Theradius of th . circle is 200 mm or a multiple of 200 mm and is as small as iscompatible with the size and position of the sample. .The tube is perforated so tha t jetsof water are directed towards the centre of the circle. and the water pressure at the inletto the apparatus is equivalent to a head of about 0 m.

M tube is caused to oscillate through an angle of J20 0 600 on either side of thevertical. the time for one complete oscillation J 20 0 x 2 being about 4 s.Th sample is mounted at the centre of the semi-circle formed by the tube. so that itslowest TNJ is level with the axis of oscillation. During the test. the sample is turnedtJbout its vertical axis or moved transversally.1 1f fediQtely afterwards the sample is subjected for 5 min to splashing in all directionsby fftlans of the splash apparatus shown in Figure 4. During this test. the water pressureis regulated that the water splashes up 15 em above the bottom of the bowl. The

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IS/lEe JOt-I ( . Ubowl is placed on a horizontal support 5 em 10 1 I'm bcl th ImH. rdg of thsample: the bowl ts moved around \ a ,l to Ipla .lh the sample from all directions . Cart' taken that the sample is not hi: by the direct .leI.

bt Watertight accessories are immersed for : 4 h in 'uter at a temperature of (I 5 'C.the highest point of the sample being about 5 em belo the -atrr level

Immediately after the treatment specified under Items a ) or b ), Ihe samples shallwithstand the dielectric strength test specified in Sub-clause 19.3. and inspectio sltall shoMOthat water has not entered the samples to any appreciable extent and has not reach ..d liveparts .

18.5 All acces sories sha ll be proof against humid cond itions which may occur in normal usc .

Compliance is checked by the humidity treatment described in this sub-clause, followedimmediately by the measurement of the insulation resistance and by the dielectric strengthtest, specified in Clause 19. Cable entries . any. are lef) open : knock-outs are provided.one of them is opened.

Covers which can be removed without the aid of a tool art' removed and subjected to thehumidity treatment with the main part ; spring lids art> open during this treatment.

The humidity treatment is carried out in a humidity cabinet conta ''''1f air wuh a relativehumidity maintained between 91 and 95 . The temperature the air. 01 all places Mhesamples can be located, is maintained within 1 C of any convenient value I Mt.un 10 Cand 30 C.

Befort' being placed in the humidity cabinet. the samples are broughl to a temperaturebetween t and t + 4 C

The samples are kept in the cabinet for:1 days 48 h) for ordinary accessories.7 days / 68 h) for all other accessories.In most cases. the samples may be brought to the temperature speCIfIed by keepln. them at Ih. . temperature

for at least 4 h before the humidity treatment.A relative humidity between 91% and 95% can be obtaiRed by placing in th e hurniduy cabinet a Iunatedsolution of sodium sulphate Na,sO. or potassium nit ra te KNO ,) IO w t r , ha vlO, a suffiCIentl y large contact

surface with the air .In order to achieve the spec ified conditions within the cabinet. it necessary to ensure constant circulat ion of

the a ir within it and. in general. to use cabinet which is thermally insulatedAfter this treatment, the samples shall show no damage witnin the meaninll this

standard.

19.1 The insulat ion resistance and the dielectric strength of accessories shall be adequate.

Compliance is checked by the tests of Sub-clauses 19.1 and /9.3. hieh are madeimmediately after the test of Sub-clause /8 .5 in the humidity cabinet or in the room in

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ISIIE 1which the samples wen broufht to the prescribed temperature, after reassembly of coverswhich may have >Hn nrtto lftl

Accessories with enclosures of thermoplastic material are subjected to the additional test ofSub-dause 19.4.

For the purpose of these tests. the neutral contact and the pilot contact are each considered as a pole.

19.2 11Ie insulation resista ce is measund with a d c voltage of approximately 500 V applied.the measurement made l min after application of the voltage11Ie ittstlMtion resistance shall be not less than 5 Mn

The term body includes all accessible metal parts, metal foil in contact with the o u t e ~ surface of e xt erna lpans of insulating material. other than the engagement face of connectors and plugs. fi ng screws of bases.enclosures and covers. external assembly screws and earth ing term inals, if any.

\92\ For socket-outlets and connectors the insulation resistance is measured consecutively:a between all ok connected together and the body. the measurement being made with

and also without a plug in engagement;b between each pole in tum and all others. these being connected to the body, with a plugin engagement;c between any metal enclosure and metal foil in contact with the inner surface of its

insulating lining. if any. a rap of approximately 4 mm being left between the metal foiland the edge of the lining:d between any metal part of the cable anchorage of connectors and metal fml wrappedround the flexible cable or a metal rod of the same diameter as the flexible cable.insertH in its place

1922 For plugs and appliance inlets the insulation resistance is measured consecutively:

a Htween all poles connected together and the body;b Htween each pole in tum and all others these being connected to the body;c between any metal enclosure and metal foil in contact with Ihe Inner surface of its

insulaling lining. if any. a gap of approximately 4 mm being lefl between th metal foiland the edge of tb lining;d between any metal part of the cable ,, chorage of plugs and metal foil wrapped round

the flexible cable or a metal rod of the same diameter as the flexible cable inserted inits place9 3 A voltage of substantially sine-wave form. having a frequency of 5 Hz 6 Hz n the

value shown in Table V is appliedfor l min between the parts indicated in Sub-clause 19.2.

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1 \ ~ t t : C\

ISIIEC lOt-I ( 9T ~ l I u V

l n vu l.n ron d I J ~ 1,1 t he' i - _ . _ .__.__ .__- ._ ....-- - .,- - - - .-- .- - .- --- . ,. . . - - . ..-_i

l r h ' ;JnJ mclu dr ng )0 '-ouo ve r u p h I 3nJ :: UUU: io ver 41 ' up It \ dnd includrn p IKI : over ) (K) .\ (lUO

The invularion voltage at least equal t the higheu rated p rattng Ita e

Th i s value increased to V Io r metal enclovures hned '-'l1h lO\uta tm grn.uerral .

Initially. no more than h lf the prescribed voltage is applied. then it is raised rapidly tothe ful l value.No flashover or breakdown shall occur during the test.Gl ow discharge, with out drop in voltage are neglected .

19.4 Immediately after the test of Sub clause 19.3, it sh all be verified that for accessories withenclosures of thermoplastic material the means of providing noninterchangeability havenot been impaired

20. re IIID capacityAccessories without interlock shall have adequate breaking capacity.

Compliance is checked by testing any accessory with a new complementary accessory thatcomplies with the relevant standard.

The test position shall be horizontal or if not possible. a.f in normal fe

ny accessory having an integral switching device operated by the plug or appliance inletshall be mounted as in normal use.

The plug or connector is inserted into nd withdrawn from the socketoutte or applianceinlet at a rate of 7.5 strokes per minute.

The speed of insertion nd separation of the plug or connector shall be n 8 It ml s.

The measurement of speed is made by recording the interval of rime between insertion orseparation of the main contacts nd the insertion . or separation of the earthing contact.relative to the distance .Electrical contacts shall be maintained for no more than 4 s nd no len than 2 s.

The two accessories shall be separated at least bv 50 mm.The number of cycles is specified in Table VJ

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IS/IEC JOt.l 1911A stroke is an insertion or a withdrawal of a plug or appliance inlet.

A cycle is composed of two strokes one for insertion and one for withdrawal.

The samples are tested at I.] times tlte rated operating voltage and 1.25 times the ratedcurrent.Accessories for a.c. only are tested with a.c. in a circuit with cos as defined in Table VI.

Accessories for d.c. only are tested with a non inductive load.Accessories having a rated operating voltage or rated current higher for a.c. than for d.c.

are tested with d.c. in a non inductive circuit. and with a.e. in a circuit such that cos isas in Table VI. A new set of accessories is used for the second test.

The test is made using the connections shown in Figure except that for accessorieshaving a rated voltage of 380 V 15 the metal support is permanently connected to theneutral. In all other cases. for two pole accessories the selector switch connecting themetal support and the accessible metal parts to one of the poles of the supply. is operatedafter h lf the number of strokes: for three pole accessories. the selector switch C is operatedafter one third of the number of strokes and again after two thirds of the number ofstrokes. so as to connect each pole in turn.

Resistors and inductors are not connected in parallel. except that. an air core in u oris used. a resistor taking approximately of the current through the inductor is connectedin parallel with it. Iron core inductors may be used. provided the current has substantiallysine wave form. For the tests on three pole accessories three core inductors are used.

During the test. no sustained arcing shall occur.After the test the samples shall show no damage impairing their further use n the

entry holes for the plug contacts shall not show any serious damage.

TABLE VIBreaking capacitytlled currentA Number of cycles

Preferred raling.\ Other ratings a.c d.c.Sene 1 Series Range cos 0.05 on load on load

16 20 up 10 9 0.6 5032 30 50from 30 10 59 0.6 50 5063 60 from 60 10 99 0.6 20 20125 100 from 100 10 199 0.7 20 20250 200 from 200 10 250 0.8 10 10

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ISII tl 1I. ormaloperation

Accessories sha ll with stand without excessive wear or other harmful effect. themechanical . electrical and thermal stresses occurring in normal use .

Compliance is checked by test ing any accessory with a It I4 complementary acussory thatcomplies with the relevant standard.This test is carried out by the same mtans as in Clause 10 used in the manner indicatedin that clause.The test posit ion is as specified in Clause 20.The test is made using the connections indicated in Clause 20 the selector switch C being

operated as prescribed in that clause.The plug or connector is inserted into or withdrawn from th socket-outlet or appliance

inlet at a rate of 7.5 strokes per minute.Accessories are submit ted alternately to cycles with and i thout current flowing except

those rated at 162 A which are only tested under load.The samples are tested at a rated operating voltage and rated current.After each 500 strokes the contacts of the plug are wiped with a piece of dry cloth.

Accessories without interlock which have been subjected to the tests of Clause 20 aretested with a number of cycles specified in Tobit VI/. Accessories for a.c. onl aft testedwith ac. in a circuit with cos { as specified in Table VII.

Accessories for d.c. only are tested with a non-inductive load.Accessories having a rated operating voltage or rated current higher for a.c. than for d.c.

are tested with both d.c. in a non-inductive circuit and with a.c. in a circuit such thatcos { is as in Table VI/. A new set of accessories is used for the second test.

Accessories with interlock are tested without current flowing the interlock being lockedand unlocked after each complete insertion of the plug.

The number of cycles is the sum of the on and off load of Table VI/.During the test no sustained arcing shall occur.After the test. the samples shall show:

- no wear impairing the further use of the accessory or of its interlock any:- no deterioration of enclosures or barriers:- no damage to the entry holes for the plug contacts that might impair proper working ;- no loosening of electrical or mechanical connections :- no seepage of sealing compound.

h samples shall then withstand an electric strength test made in accordance withSub-clause /9.3. the test voltage however being decreased by 500 V for accessories havingan insulation voltage exceeding 50 V.

The humidity t reatment is not repeated r o r ~ the electric strength ICSl or lh i, sub-clause

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IMI:C 3091 19 ). . .r d b completell opening and closing the lid. the number ofLId springs . I any. are teste y . . ifi .. . the same as the number of mseruons of the plug spec I led Inrimes the lid IS opene eingTable VI/.

Th te t may be combin ed with the test for the accessories .

T ABLE VIINormal operation

i Rated current Number ofAPreferred Other a.c. d.c.ra ting rat ing

Series \I Range cos j on load off load on load of f loadSeries I .05i16 I 20 up to 29 0.6 5 5 -32 30 30 to 59 0.6 1 000 1 000 1000 1000

63 I 60 60 to 99 0.6 I 1 1000 500 500125 100 100 to \99 0.7 250 250 250 250250 200 200 to 250 8 125 125 125 12522. per t re rise

Accessories shall be so constru cted that the temperature rise in normal use is notexcessive.

Compliance is checked by testing any accessory with a new complementary accessory thatcomplies with the relevant standards.

Ie test current is an alternating current of the value shown in Table V l .Re tirable accessories are fil led with conductors of a cross-sect ional area as specified in

Table V/I I the terminal screws or nuts being tightened with a torque equal to two-thirds oftltal specified in Sub-clause 25.1.

For the purpme of tkis test. a length of at least 2 m of the cable is connected to theterminals.

Non-re...-irable access ories are tested as delivered.For accessories a ving three or more poles. the test current dllring the test shall be passed

thrQugh the phase contacts. f there is a neutral contact. a separate test shall be carried outpani g the test current through the neutral contact and the nearest phase contact.

A further separate test shall be carried out passing the test current tltf Ugh the earthingcoetact and the nearest phase contact.

A current of 2 A shall be passed througb the pilot contact. any, at the same time asany of these tests.

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IS/lEe 309-1 1988T LE VIII

Cro ss-sectio na l area s) of th e conductor sPreferr ed Test

rated curren t c urrent A) A)PlugsAppli ance inl ets Socke t-out lets

Con necto rsSeries I Se ries II mm mm

16 20 22 2.5 ) 4 )32 30 42 6 ) 1063 60 rat ed current 16 25125 100 rated cu rrent 50 70250 200 rated current 150 185)

I ) For accessories havin g a rated opera ti ng voltage not exceeding 50 V. th e val ues a re increas ed t o 10.z 150 mm for 200 A Ser ies II.

The duration of the test is: 1 h for accessories having a rated current not exceeding 32 A;2 h for accessories having a rated current exceeding 32 A but not exceeding 125 A;3 h for accessories having a rated current exceeding 125 A

The temperature is determined by means of melting particles colourchanging indicatorsor thermocouples which are so chosen n positioned that they have negligible effect on thetemperature being determin ed

The temperature rise of terminals shall not exceed 50 K

23. Flex ible cables an d thei r connection23.1 Plugs and connecto rs sha ll be provided with a cable anchorage such that th e conductors

ar e relie ved from strain, including twisting, where th ey are connected to the terminals orterminations, and that th ei r c over ing is p rot ec te d from abrasion.

Cable anchorages shall be so d esigned that the cable cannot touch acce ssible metalparts or internal metal parts, for example c able a nc ho ra ge scr ews, if these are electricallyc on ne ct ed to a cce ssi ble metal p ar ts, un less the acce ssible metal parts -are connected to theinternal earth terminal.

Compliance is checked by inspection

23.2 R eq ui re me nts for plugs and connector 3 Non rewirable plugs n connectors

Accessories shall be p ro vided with a Oexible cab le complying with IE C Pub lication 245-4of one of the types specified in the following table, the nominal cro ss-sectional areabeing not less than the valu e sho wn .

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ISIIEC 309-1 1911T.-\ lU IX

ln lt rrt r.ned curr ent , ..-\

TH ,, ca ble Nominal cross-section.. ...__.,

II C2.5 1161650

150

iiI

5J . 57 . :>53 . 06Ill>:>06

zo.illotJ100200

II

oJ

L._. ._ _ .. _ - - - _ -\ cce, ,, , , ie hJ J ra ted ope ra t ing voltage not exceed ing 50 V. va lue increased to 4.

, , a pp licable to JCIe. Orte, hav ing a ra ted opera ting vo ltage exceeding 4 15 V. O n I applicable for .\ P J a nd P J.. On app licab le fo r 3 p J. , For non -prefe rred curren t ra t ings. val ues are under considerat io n.

Flexible cables having nominal cross-sections other than those specified in Table IXmay be used if the load is known.

The core connected to the earthing terminal shall be identified by the colourcombination green yellow. The nominal cross-sectional area of the earthing conductor andof the neutral conductor. if any. shall be at least equal to that of the phase conductors.

The pilot conductor. if any. shall have a nomin al cross-sectional area of at least 5

Compliance is checked by inspection and by the test of ubclause 233

Rewirable plugs nd connectorsit sha ll be clear how the relief from st rain and the prevention of twisting is intendedto he effected :

- cable anchorages shall present no sharp edges to the cable and shall be so designedthat the anchorages or their components cannot be inadvertently lost when theaccessory is being dismantled :

- makeshift methods. such as tying the cable into a knot or tying the ends with string,shall not he used :

- cable anchorages and cable inlets sha ll be suitable for the different types of flexiblecable which may be connected .If a cable inlet is provided with a sleeve to prevent damage to the cable, this sleevesha ll be of insulating mater ial and sha ll be smooth and free from burrs.If a bell-mouthed opening is provided. the diameter at the end shall be at least 1.5 times

the diameter of the cable with the largest cross-sectional area to be connected.Helical metal sp rings. whether bare or covered with insulating material, are not a llowedas cable sleeves.Compliance is checked by inspection and by the test of Sub clause 23 3

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lSIlEC )091 ( 1911 )23.3 Plugs and connectors provided with a fl e xible , M are .Iub III a pull tcvt apparatussimilar to that shown in Figure 6, [u lloH bv a torqu t '.I;

Non-rewirable accessories are tested as delivered.Rewirable accessories are tested firs t with one and then wtt the oth er tvpe (If cable,complying with l E Publication 245-4, as speci fied in TaM.. X.

TABLE X

i : p+ J.PPm

crosssection

Type ofcable

I EC 245eries II

Preferred rat edcurrent

A

Seri es I

. - - - .-- - - -------,. - - - - .- - - .- .- --- .._ ..__..._.__.....- ...No mi na l App ro llm att' ex re rna1 d iameter \ \f t he l.dN e I

1 - - _ ( _ _ \ ( ~ _-_ ',--_------1Not

exceedi ng50 V

1632

2030

66666666

410410

135213213

12.52.56 .06 016165070

ISO

536653666666666666

20

6030

200100

\ 6

6332

125250

Over50 V

, S I I IU, , 10 0II 1. 0 14.0 140I )7.1 : I : 13I i E ~ 1 E 11 J W 3 li I 4 , 4H HL . . . - --- -- - - - - . . l Li _ ~ ~ .. ~ ~' ) The value for each of the approximate external d iameters shown i, the average value of the urp' and lo e, IIm,tospecified in IEC Publication 2454 for the overall diameter of the cable

II Values ar e under con side ration .

Conductors of the cable of rewirable accessories are introduced into th terminals, theterminal screws being tightened just suffic iently to prevent the conduc tors from easilychanging their position.

The cable anchorage is used in the normal way, clamping screws being IIghlened with atorque equal to two-thirds of that specified in Sub-clause : .1. After reassembly of thtsample. with cable glands, if any. in position, the component parts shall fi t .rnugly and itshall not be possible to push the cable into the sample to any appreciable extent.

The sample is fixed in the test apparatus so that tht axis of the cable is vertical where itenters the sample,

The cable is then subjected 100 times to a pull of th value shown in the table below.Each pull is applied without jerlcr and has a duration of I s,

Immediately afterwards. the cable is subjected for I min to a torque of th value shownin the following table.

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ISIIEC 09.1 1988T LE XI

Pretcrred r.tleJ cu rrent\ Force

Sene -, Sene s II II> SO

.\0 10063 eo100 100100 00

TorqueN m0.3 5OA250.81.53

During the tests. the cable shall not be damaged.A in the tests. the cable shall not have been displaced by more than 2 mm . For rewirable

accessories , the ends of the conductors shall not have moved noticeably in the terminals: fornon-rewirable accessories. there shall be no break in the electrical connections.

For the measurement of the longitudinal displacement. a mark is made on the cable at adistance of approximately ;} em from the end of the sample or the cable anchorage beforestarting the tests. If for non-rewirable accessories. there is no definite end to the sample, anadditional mark is made on the body of the sample.

After the tests , the displacement of the mark on the cable in relation to the sample orthe cable anchorage is measured.

14. Mechanical strength:: 4 .1 Accessories shall have adequate mechanical strength.

Compliance is checked by the appropriate test s of Sub-clauses 24.2 to 24.5 as follows :

. fo r socket -outlets and appliance inlets. Sub-clause 24.2 :

.- fo r re...irable plug s and connectors, Sub clause 24.31}:[o r non-re -irable plugs and connectors, Sub-clauses 243 1 and 24.4 :

. [or glands of splashproo] and watertight accessories, Sub-clause 24.5:- for accessories ith a degree of protection higher than I PXV Sub-clause 245

Before starring the test of Sub-clause 24.2 or 24.3. accessories with enclosures of resilientor thermoplastic material are placed. with their bases or flexible cables. in a refrigerator ata temperature - 25 ;: C for at least 16 h; they are then removed from the refrigeratorand immediately subjected to the test of Sub clause 24.2 or 24.3. as appropriate.

141 Blo are applied to the samples by means of the spring-operated impact test apparatusshown in Figure 7.

The apparatus consists of three main parts: the body, the striking element and thespring-loaded release cone.

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1S/I}:C JOt1 ( U The body comprises the housing. the striking element guide. the release mechunism and

all parts rigidly fixed hereto . The ma .\\ of this assemblv is 1 g.The striking element comprises the hammer head. the hammer ,lhaJi and ,hc cocklnllknob . The mass of his assembly is g.The hammer head has a hemispherical face of polyamide hal ing a Rockwell hardness ofHR 100. with a radius of 10 mm; i is f ixed to he hammer shaft in such a Itu r that he

distance from its tip to he plane of the front of he cone. when he striking elemen is onthe point of release, is 28 mm.The cone has a mass of 60 g and the cone spring is such that it exerts u force f N

when the release jaws are on the point of releasing the striking dement.The hammer spring is adjusted so that the product of the compression. in millimetres. and

the force exerted. in newtons, equals 2 000, the compression being approximately 28 mm .With this adjustment, the impact energy is I 1.05 Nm.

The release mechanism springs are adjusted so that they exert just sufficient pressure tokeep the release jaws in the engaged position.The apparatus is cocked by pulling the cocking knob until th release jaws t ngagt .;Ih

the groove in the hammer shaft .The blows are applied by pushing he release cone against the sample in a direction

perpendicular to the surface at the point to be tested.The pressure is slowly increased so that the cone moves back until it is in contact It ilh

the release bars, which then move to operate the release mechanism and a/lo tht hammt rto strike.

The sample is fixed as in normal use to a rigid support. Cable entries are It jt open andf ixing screws of covers and enclosures are tightened It ith a torque equal to two-thirds ofthat specified in Table X/V.

Three blows are applied to every point that is likely to be weak.After the test, the samples shall show no damage within tht meaning of this standard; in

particular. live parts shall not have become accessible and the enclosure shall .rhow 1cracks visible to tlte naked eye.

Watertight accessories and those with a degree of protection IPX7 and above shallwithstand the relevant treatment specified in CIIW e 18.

Accessories with enclosures of thermoplastic material shall wiUuu..d the teat ofSub-clause 19.4.

Damage to the finish, small dents whi

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ISIIEC 309-1 9The sample is held so that the cable is horizonta and then it is allowed to fall on to a

concrete floor This is done eight times. the cable being rotated through 45 at its fixingeach time.f t r the test. the samples shall show no damage within the meaning of this standard; in

particular. no part shall have become detached or loosened.Watertight accessories and those with a degree of protection IPX7 and above shall

withstand the relevant treatment specified in Clause 18.Accessories with enclosures of thermoplastic material shall withstand the test of Sub-clause

9ASmall hip and dents which do not adversely affect the protect ion against electric shock or moisture are

neglected.24.4 Non-rewirable accessories are subjected to a flexing test in an apparatus similar to that

shown in Figure 9.The sample is f ixed to the oscillating member of the apparatus so that, when this is atthe middle of its travel. the axis of the flexible cable, where it enters the sample, is vertical

and passes through the axis of oscillation.The oscillating member is so positioned that the flexible cable makes the mlmmum lateral

movement when the oscillating member of the test apparatus is moved over its full travel.

The cable is loaded with a weight such that the force applied is as shown in thefollowing table.

T LE XIIPreferred rated urrent Force

A NSeries I Series II

6 20 2032 30 25

A current equal to the rated current of the accessory is passed through the conductors.the voltage between them being the rated voltage.

The oscillating member is moved backwards and forwards through an angle of 90 (45on either side of the vertical), the number of flexings being 20 and the rate of flexing60 per minute.

After the test, the samples shall show no damage within the meaning of this standard.

A Ilexing is one movement e ither backwards or forwards.For accessories having a rated cur rent exceeding 32 A. details of the test are under conside rat ion .

24.5 Screwed glands are filled with a cylindrical metal rod having a diameter. in millimetres, ~ ~ to the nearest whole number below the internal diameter of the packing; in~ I m e t r e s . glands are then tightened by means of a suitable spanner, the force shownrn the following table being applied to the spanner for I min, at a point 5 cm from theaxis of (he gland.

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L \IIEC JOt1 IT LE XIII

20304

ForceN

3045011

M ~ l 1 glandsmm

iameteroftest rod

Up to and including 20Over 20 up toand including 30Over 30

__ _ - - . ..__. - -.._ .. - - . .- ...- - ..... 1

_ Gland o f I

mt>uldC\l m I ~ f il l L J

II These values arc provisional.

After the test, the glands and the enclosures of the samples shall show no damage withinthe meaning of this standard.

25. Screws curreDt-carryiDg parts aDd coaDeCtiollS25.1 Connections electrical or otherwise shall withstand the mechanical stresses occurring in

normal use.Screws transmitting contact pressure and screws which are operated when connecting

up the accessory and have a nominal diameter less than 3.5 mm shall screw into a metalnut or metal insert.

Compliance is checked by inspection and. for screws and nuts transmitting contact prnSIUYor which are operated when connecting up th accessory. by the following test.

The screws or nuts are tighit ned and loosened:- ten times for screws in engagement with a thread of insulat; , material:- five times for nuts and other screws.

Screws in engagement with a thread of insulating material are completely r e m o l l ~ a.nJreinserted each time.

This removal and insertion of the screws or nuts shall be carried out at such a rate thatthe thread in the insulating material suffers no appreciable temperature rise owing friction.

When testing terminal screws and nuts. a copper conductor hamsg the la'6estcross-sectional area in Table Ill rigid (solid or stranded) for socket-outlets and applianceinlets and flexible for plugs and connectors, is placed in 'he terminal.

The test is made by means of a suitable scrrNdriver or spanner. The maximum 'orqueapplied when tightening is equal to that shown in 'he Table XIV except hat 'he torque isincreased by 20% for screws in engagement with a thread in a hole which obtained byplunging, the length of the extrusion exceeds 80% of the original thickness of the metal:

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IS /IEC 3091 1T LE XIV

i , To rqueI I Nominal d iameter II N mI srandard of threadI val ue-, mmrI I II II II L p 10 and including 0.2 0.4 0.43.0 up to and includ ing 3.0 0.25 0.5 0.5over 0.6 0.6.0 up to and including 0.3I - over 0.8 0.83 5 over up 10 and including 3.6 0.4

4 0 3.6 up to and includ ing 4.\ 0.7 L2 L2verU 4.\ up to and including 4.7 0.8 1.8 1.8\ 5.0 4.7 up to and including 5.3 0.8 2.0 2.0\0 r6 ov er 5.3 up 10 and includ ing 6.0 2 2.5 3.0 0 over 6.0 up 10 and includ ing 8.0 2.5 3.5 6.0I 10.0 over 8.0 up 10 and includ ing 10.0 4.0 10.0over 10.0 up to and including 12.0 \4.0

14.0 over 12.0 up 10 and including 15.0 19.016.0 ov er 15.0 up to and includ ing 20.0 25.0z o over 20.0 up to and including 24.0 36.024 over 50.0

Column I

Column

Column

applies to screws without heads which when tightened do not protrude fromthe hole. and to screws which cannot be tightened by means of a screwdriverhaving a blade wider than the diameter of the screw.applies to other screws and nuts which are tightened by means of ascrewdriver.applies to screws and nuts which can be tightened by means other than ascrewdriver.

Each time the clamping screwis or nutts is are loosened. a new conductor shall beused for a further connection.When a screw has a hexagonal head with means for tightening with a screwdriver and

the values in columns II and are different. the test is made twice, first applying thetorque specified in column to the hexagonal head and then. on another set of samples.applyin Ihe torque specified in column II by means of a screwdriver. f the values incolumns II and are the same. only the test with the screwdriver is made.

After the test for clamping screws or nuts. the clamping unit shall not have undergonechanges thai adversely affect its f urther use.For mantle termi nals, the speci fied nomi na l d iameter is tha t of the slotted stud ,For mant le term inal s in which the nut is lightened by means ot he r than a screwdriver and for whi ch thenom ina l sere di amet er is over 10 mm . the value of the torque is unde r con sideration.Screws o r nuts wh ich are operated when con necting up the accesso ry inc lude term inal screws or nuts. assembly

screws. screws for fix ing coven etc. but not connections for screwed conduits and screws for fixing socket-outletsor appl iance inlets 10 the mount ing surface.

The shape of the blade of the test screwdriver shall suit the head of the screw to betested .The screws and nuts shall not be tightened in jerks.Damage 0 cover s IS neglected .

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ISIIEC )091 ( It1125.2 Screws in engagement with a thread of insulating material and which are operated when

connecting up the accessory shall have a length of engagement of at least J mm plusone-third of the nominal screw diameter, or 8 mm, whichever is the shorter.

Correct introduction of the screw into the threaded hole shall be ensured.Compliance is checked by inspection. by measurement n by manual ten .The requirement with regard to correct introduct ion is mCI If mtroducuon of the .ere rn a ,lanlln, manner

is prevent ed , o r example by guiding the screw by tbe pan 1 be fixed. a recess In ine th rcad cd ho le or bythe usc of a screw with tbe lead ing thread removed .

25.3 Electr